What is a freshwater crayfish called?

Do pet store's sell male and female guppies? What kind of shark bit Rodney fox? What is the plural form of Koi? If the first 2 fish that you caught were less than 44 mm long would you be suspecious of the claim of the mean of 54 mm Explain with a probability argument.? What do Fiddler crabs do with their one large claw? Do sand crabs need air? Can you use sea salt non iodized for hermit crabs? Are Tiger Sharks vertebrates? Is bait a plural noun or a singular noun? How does a fish survive in the midnight zone? What are the Advantages and disadvantages of cage use in aquaculture? Do stingrays have flippers? How often does a guppy's tank need to be cleaned? Why do fish pen owners are worried of monsoon? Do fish have back bone? Does nagisa find out hano is a mermaid? Can sharks swim without dorsal fins? How do you tell if a bass is a male or female? What kind of mammals do great white shark eat? Do the piranha change color with the seasons?